THE FAMIT.Y OF EELS. 
313 
mentioned, until the autumnal eqviinox; beyond which no more 
have been discovered. The hindrances here referred to are the 
accident of a muddy condition of the water, which is distasteful 
to the old Eels as well as to the young, so that the former 
will quit a river or pool to avoid it; and also a very low state 
of the stream, when they do not avoid it or lie still from the 
merely deficient quantity of water, for a dribbling of what is 
pure will lead them onward, but from its polluted condition, 
of which these fish are quickly sensible. When thus situated 
in consequence of the dryness of the season, no Eels have 
been seen to pass for five or six weeks; while afterwards an 
abundant fall of rain has been soon followed by an upward 
migration; which at this early stage of their existence appears 
to be essential to their well-being. 
But although delayed by a muddled or nauseous condition 
of the water. Eels are not to he hindered by mechanical 
difficulties; and it is amusing to trace the means to which they 
have recourse in passing over barriers that might seem inac- 
cessible to their efforts. It was at a time when a moderate 
but rapid stream had from dry weather become a small cascade, 
that the only way of ascent was up the declivity of a perpen- 
dicular rock, from which on one side hung some moss and 
herbage into the water below. When these Eels in succession 
came to this place they moved about rapidly near where the 
stream fell down from above, and presently disappeared; when 
looking more closely it was seen that on one side of the pro- 
jecting rock they had crept among the fibres of the moss that 
hung downward, and were moving upwards with wriggling 
motion, like worms; but resting at times and taking care to 
keep at a safe distance from the falling current. At last they 
reached the top and settled into rest, with the head a little 
stretched out into the river; but after a time, seizing a favourable 
moment of recovered energy, they put out their renewed strength 
and moved upward in the stream. Those of them, however, 
which had taken the other side of the rock were differently 
situated, and their task was to thrust themselves over a sloping 
surface by dint of their unaided exertions; in accomplishing 
which some quitted the water altogether; but they still kept 
on a moist portion of the ascent, up which by a slow and 
laboriously serpentine action they contrived to urge their way 
VOL. IV. 2 s 
